This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. This supplemental request provides funding to enable us to complete Specific Aim 1 of the parent grant that was approved at the beginning of the award on July 1, 2006. The goal of this specific aim is to use transgenic GnRH-GFP rats and electrophysiological techniques to record from GnRH cell bodies and determine the direct effects of various neuropeptides related to regulation of reproduction and energy homeostasis. The hypothesis of this specific aim is that the orexigenic (NPY, orexin, MCH) and anorexigenic (NKB) neuropeptides are key signals linking energy balance and reproductive function through direct actions on GnRH neurons. These supplemental funds allow us to have a fully functional electrophysiology set up in our laboratory with a full time staff fellow, Dr. Verma, dedicated to these studies. With the addition of the funded equipment items, we are able to perform all the studies proposed in this grant. In addition, with the recruitment of Dr. Matsumoto as a Co-Investigator, an expert in electrophysiology techniques we have the expertise to supervise this work and guide us in the design of future experiments. With our own set up and personnel, we will be able to make much greater progress and to explore additional factors, such as kisspeptin, and to study interactions of presynaptic and postsynaptic effects on GnRH activity of factors such as neurokinin B and kisspeptin, or NPY's actions through presynaptic Y1 and postsynaptic Y5. Completion of these studies is critical to our understanding of the key neuropeptides that directly regulate GnRH.